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I'm looking for a material or compound, whose dielectric constant multiplied by the square if its dielectric strength (MV/m) is greater than two billion at temperature from -20C to 100C.

It doesn't matter whether the individual values of dielectric strength or dielectric constant are high or low, I'm only interested in the final value.

Also frequency is not a consideration, since this is not for AC use.

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  • \$\begingroup\$ I don't know how Mica fares but if it doesn't suffice "there may be problems". \$\endgroup\$
    – Russell McMahon
    Commented Mar 23, 2017 at 8:14
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    \$\begingroup\$ Take diamond with 16,5 * 2000^2 = 66*10^6 \$\endgroup\$
    – Don
    Commented Mar 23, 2017 at 8:53
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    \$\begingroup\$ Sounds more like "Please internet, it's so much work looking through material tables, please do the work for me"? \$\endgroup\$
    – pipe
    Commented Mar 23, 2017 at 9:07
  • \$\begingroup\$ Can you tell me what tables you are taking about? I've not come across any tables that have a material that fits the bill, I've probably spent over 100 hours searching the net. So maybe looking through material tables isn't that much work, but finding them is. \$\endgroup\$
    – Cassie
    Commented Mar 23, 2017 at 10:11
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    \$\begingroup\$ A sufficiently good vacuum would appear to fulfil the requirements. \$\endgroup\$
    – user16324
    Commented Mar 23, 2017 at 11:03

3 Answers 3

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If by dielectric strength you mean V/m then"it's easy".
If you mean MV/m then probably only diamond has a chance of qualifying, and probably doesn't.

Here is Wikipedia DS page.
The table of strengths indicates that for diamond to be suitable the dieletric constant would need to be.

2,000,000,000/2000^2 = 500

Reported values are in the 5 - 10 range.

enter image description here


Another approach is to look at material with high DC as a starting point.
Barium titanate is one of the highest wity reported values in the 4000-6000 range. As this is usually sintered from a powdered form air voids and similar affect results.
Dielectric strength is not marvellous [tm] but eg this paper Improved dielectric strength of barium titanate-polyvinylidene fluoride nanocomposite using barium titanate reports

  • Barium titanate-polyvinydene fluoride nanocomposites with improved dielectric strength were prepared, in which on the surface of the barium titanate nanoparticle was coated. The results showed that the dielectric breakdown strength of the nanocomposites increase significantly up to 250 kV/mm and then decrease.

250 kV/mm = 250 MV/m. At say (one can hope) DC of 6000 that still gives a figure of merit of 6000 x 250^2 = 375 million, or only about 20% of your target value.

As the greatly improved DS is achieved by coating and thus disprsing the barium titanate particles within the polyvindene I'd expect that the DC would be much lowered.

enter image description here

From here


Barium Titanate:

http://www.intechopen.com/books/ferroelectrics-material-aspects/barium-Barium Titanate-Based Materials – a Window of Application Opportunities

The Overview of The Electrical Properties of Barium Titanate

Dielectric and Piezoelectric Properties of Barium Titanate

https://en.wikipedia.org/wiki/Barium_titanate

Possible interest

Giant polarization in high polymers

Diamond

http://www.nature.com/nature/journal/v161/n4097/abs/161729a0.html

http://pubs.rsc.org/en/content/articlelanding/1940/tf/tf9403500575#!divAbstract

Reference:

https://en.wikipedia.org/wiki/Dielectric_strength

Silver Mica Capacitor - an overview or tutorial about the basics of the silver mica capacitor, its construction, properties and the uses of silver mica capacitors particularly in RF circuits.

Mica

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This is limited to R&D use at present.

Aromatic polyurea thin films were developed through vapor phase deposition, exhibiting relatively high dielectric constant, low loss, high breakdown field (>800 MV/m) and consequently high energy density (>12 J/cm3).

High energy density dielectric materials are desirable for capacitors and other energy storage systems. Two approaches were developed to achieve high electric energy density: explore high dielectric constant (K) materials and improve high operation electric field.

ref http://aip.scitation.org/doi/abs/10.1063/1.4961252?journalCode=apl

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I found a paper by Natalie Jenkins at the Department of Mechanical Engineering, Naval Postgraduate School.

Fumed silica wetted to incipient wetness, with a saturated NaCl solution has a dielectric constant > 10,000,000,000, and a dielectric strength > 2.3 MV/m.

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